1. Field of the Invention
The present invention relates to a semiconductor chip with a porous single crystal layer and manufacturing method of such a chip.
2. Related Art
In the process of manufacturing, processing or the like of a semiconductor wafer, a porous single crystal layer may occur in the semiconductor wafer. The porous single crystal layer becomes hindrance to junction in installing a plug in a semiconductor chip obtained from the semiconductor wafer, or the like, and therefore, is removed in the process of manufacturing, processing or the like of the semiconductor wafer. Hence, the semiconductor chip is typically not provided with the porous single crystal layer (JP H10-335632).
However, the semiconductor chip provided with the porous single crystal layer has been proposed in the case of semiconductor chips such as a photodiode dedicated to very limited applications. The porous single crystal layer has the property of converting a light beam with short wavelengths into a visible light beam. To use the property, it is an indispensable requirement to provide the porous single crystal layer to come into contact with an impurity region prepared on a main surface portion of the semiconductor chip (JP 2004-214598).